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Particulate matter concentrations originating from industrial and urban sources: Validation of atmospheric dispersion modeling results Texto completo
2016
Abril, Gabriela A. | Diez, Sebastián C. | Pignata, María L. | Britch, Javier
This study presents the analysis of the emission, transport, dispersion, and concentration of particulate matter emitted from a large industrial complex dedicated to the manufacture of cement in the town of Malagueño, province of Córdoba (Argentina), using the USEPA's (Environmental Protection Agency) AERMOD model. The model was applied for 224 industrial and background emission sources (8 stacks, 3 limestone quarries, 13 material storage piles, 18 agricultural fields and 182 paved and unpaved segment roads). The application of the model was validated with Total Suspended Particulate matter (TSP) measured at two monitoring sites, where samples were collected for 62 consecutive days in winter. The maximum TSP values obtained at both monitoring sites (748 and 1100 μg m−3) were well above the suggested WHO guidelines. The results obtained showed the impact of this industrial activity on local particulate matter concentrations, from which unpaved industrial roads and stockpiles were the most influential emission sources, directly affecting two of the closest neighborhoods in the area. Future studies will include the accumulation of heavy metals and Polycyclic Aromatic Hydrocarbons in TSP samples, the environmental risk assessment for exposure of the Malagueño population and the source apportionment of these pollutants.
Mostrar más [+] Menos [-]Chemical contaminants entering the marine environment from sea-based sources: A review with a focus on European seas Texto completo
2016
Tornero, Victoria | Hanke, Georg
Anthropogenic contaminants reach the marine environment mostly directly from land-based sources, but there are cases in which they are emitted or re-mobilized in the marine environment itself. This paper reviews the literature, with a predominant focus on the European environment, to compile a list of contaminants potentially released into the sea from sea-based sources and provide an overview of their consideration under existing EU regulatory frameworks. The resulting list contains 276 substances and for some of them (22 antifouling biocides, 32 aquaculture medicinal products and 34 warfare agents) concentrations and toxicity data are additionally provided. The EU Marine Strategy Framework Directive Descriptor 8, together with the Water Framework Directive and the Regional Sea Conventions, provides the provisions against pollution of marine waters by chemical substances. This literature review should inform about the current state of knowledge regarding marine contaminant sources and provide support for setting-up of monitoring approaches, including hotspots screening.
Mostrar más [+] Menos [-]Metal contaminant fluxes across the sediment water interface Texto completo
2016
Frogner-Kockum, Paul | Göransson, Peter | Åslund, Henrik | Ländell, Märta | Stevens, Rodney | Tengberg, Anders | Göransson, Gunnel | Ohlsson, Yvonne
To date, most estimates of contaminant fluxes across the sediment/water interface in risk assessments have been done using diffusive flux models. However, the reliability of these is limited as the overall flux from the sediment may have contributions caused by advection and bioturbation. We found through a comparison of modelled fluxes versus measured fluxes, that the methods Benthic Flux Chamber and surface leaching tests in a risk assessment context showed similar magnitude while calculated fluxes deviated at least by a factor of 100 from measured fluxes. This may be explained by the flux contribution in connection with bioturbation. The chamber-measured fluxes of copper were low compared to those of zinc and cobalt, but this is consistent with leaching tests that indicated copper to be more strongly bound. Risk assessments based on total concentrations may be misleading.
Mostrar más [+] Menos [-]Changes in the distributions of juvenile horseshoe crabs (Arthropoda: Chelicerata) (2002–2014) related to environmental perturbations at Pak Nai and Ha Pak Nai, Deep Bay, Hong Kong SAR, China Texto completo
2016
Lee, Christine Nga-Wing | Morton, Brian
A survey of juvenile Asian horseshoe crabs in 2002 on the mudflats along Hong Kong's north-western shoreline abutting Deep Bay identified two species, Tachypleus tridentatus and Carcinoscorpius rotundicauda, and assessed their population characteristics. Since the 2002 survey, there have been significant habitat changes to this natal site for the two species. By employing the same, but expanded, sampling protocol, a further survey was, therefore, conducted twelve years later in 2014. A general population decline was recorded for T. tridentatus whereas for C. rotundicauda there was an increase and its distribution had become more widespread. The distribution patterns of the two species were also shown to have changed. The potential factors that might be responsible for recorded changes in the species' population characteristics between 2002 and 2014 are related to anthropogenic perturbations, including environmental habitat alterations notably the building of a bridge linking Hong Kong to Shenzhen in China.
Mostrar más [+] Menos [-]Persistent organic pollutants and inorganic elements in the Balearic shearwater Puffinus mauretanicus wintering off Portugal Texto completo
2016
Costa, R.A. | Torres, J. | Vingada, J.V. | Eira, C.
This study presents the first data on trace element and organic pollutant concentrations in the Critically Endangered Balearic shearwater Puffinus mauretanicus collected in 2010 and 2011 in Portugal. Trace element levels were below the threshold levels for adverse effects on birds, despite the Hg concentrations in feathers (4.35μg·g–1ww). No significant differences were detected between individuals from 2010 and 2011 except for Se concentrations in liver, feathers and muscle (higher in 2010) and Ag in liver and muscle (higher in 2011). No significant differences were detected in total concentrations of organochlorine compounds in Balearic shearwaters between years, although PCB congeners -101 and -180 presented higher concentrations in individuals from 2010. The PCB congeners -138, -153 and -180, and 4.4-DDE were detected in all individuals. This study on toxic elements and organic pollutants in wintering Balearic shearwaters provides baseline data from which deviations can be detected in the future.
Mostrar más [+] Menos [-]Antibiotic Residues in Animal Waste: Occurrence and Degradation in Conventional Agricultural Waste Management Practices Texto completo
2016
Van Epps, Amanda | Blaney, Lee
The presence of antibiotics in animal manure represents a significant concern with respect to the introduction of antibiotic residues to the environment and the development of antibiotic-resistant pathogens. In this review, we have (1) compiled reported detections of antibiotics in poultry litter, swine manure, and cattle manure; and (2) discussed the treatment of antibiotics during conventional agricultural waste management practices. The most reported antibiotics in animal manure were fluoroquinolones, sulfonamides, and tetracyclines, all of which the World Health Organization has listed as critically important for human health. Relatively high treatment efficiencies were observed for antibiotics in composting, anaerobic digestion, and aerobic/anaerobic lagooning. Interestingly, active management of compost piles did not demonstrate a significant increase in antibiotic degradation; however, low- and high-intensity compost systems exhibited high treatment efficiencies for most antibiotics. Anaerobic digestion was not effective for some key antibiotics, including lincosamides and select sulfonamides and fluoroquinolones. Given the potential for energy recovery during anaerobic digestion of agricultural waste, efforts to optimize antibiotic degradation represent an important area for future research. Lagoons also exhibited fairly high levels of antibiotic treatment, especially for aerobic systems; however, the operational costs/complexity of these systems inhibit utilization at the full-scale. No overall trends in antibiotic treatment efficiency during these three agricultural waste management practices were observed. Finally, we posit that increased efforts to include analysis of antibiotic residues in animal manure in national surveillance programs will provide important information to address concerns over the continued use of antimicrobials in animal feeding operations.
Mostrar más [+] Menos [-]Oman's coral reefs: A unique ecosystem challenged by natural and man-related stresses and in need of conservation Texto completo
2016
Burt, J.A. | Coles, S. | van Lavieren, H. | Taylor, O. | Looker, E. | Samimi-Namin, K.
Oman contains diverse and abundant reef coral communities that extend along a coast that borders three environmentally distinct water bodies, with corals existing under unique and often stressful environmental conditions. In recent years Oman's reefs have undergone considerable change due to recurrent predatory starfish outbreaks, cyclone damage, harmful algal blooms, and other stressors. In this review we summarize current knowledge of the biology and status of corals in Oman, particularly in light of recent stressors and projected future threats, and examine current reef management practices. Oman's coral communities occur in marginal environmental conditions for reefs, and hence are quite vulnerable to anthropogenic effects. We recommend a focus on developing conservation-oriented coral research to guide proactive management and expansion of the number and size of designated protected areas in Oman, particularly those associated with critical coral habitat.
Mostrar más [+] Menos [-]Species-specific trends in the reproductive output of corals across environmental gradients and bleaching histories Texto completo
2016
Howells, Emily J. | Ketchum, Remi N. | Bauman, Andrew G. | Mustafa, Yasmine | Watkins, Kristina D. | Burt, John A.
Coral populations in the Persian Gulf have a reputation for being some of the toughest in the world yet little is known about the energetic constraints of living under temperature and salinity extremes. Energy allocation for sexual reproduction in Gulf corals was evaluated relative to conspecifics living under milder environmental conditions in the Oman Sea. Fecundity was depressed at Gulf sites in two Indo-Pacific merulinid species (Cyphastrea microphthalma and Platygyra daedalea) but not in a regionally endemic acroporid (Acropora downingi). Gulf populations of each species experienced high temperature bleaching at the onset of gametogenesis in the study but fecundity was only negatively impacted in P. daedalea and A. downingi. Large population sizes of C. microphthalma and P. daedalea in the Gulf are expected to buffer reductions on colony-level fecundity. However, depleted population sizes of A. downingi at some Gulf sites equate to low reef-wide fecundity and likely impede outcrossing success.
Mostrar más [+] Menos [-]Effects of Costa Concordia shipwreck on epiphytic assemblages and biotic features of Posidonia oceanica canopy Texto completo
2016
Bacci, T. | Penna, M. | Rende, S.F. | Trabucco, B. | Gennaro, P. | Bertasi, F. | Marusso, V. | Grossi, L. | Cicero, A.M.
This research provides first information about Posidonia oceanica canopy in the area affected by Costa Concordia wreck. Percentage cover of algal and animal taxa on the leaves was estimated and biotic features of the meadow were measured in the period just after the shipwreck until its removal from the impacted site. Changes in epiphytic assemblages and some biotic features were detected in the Disturbed site compared with Control ones, highlighting effects due to the wreck presence and activities related to its removal. A temporary decrease of encrusting macroalgae and an increase of erected macroalgae and foraminifers, as well as a temporary increase of tip erosion of the canopy were detected in the Disturbed site. The obtained results were discussed and hypotheses about possible synergic effects occurred near the wreck were commented.
Mostrar más [+] Menos [-]A surface tension based method for measuring oil dispersant concentration in seawater Texto completo
2016
Cai, Zhengqing | Gong, Yanyan | Liu, Wen | Fu, Jie | O'Reilly, S.E. | Hao, Xiaodi | Zhao, Dongye
This work developed a new method to determine concentration of Corexit EC9500A, and likely other oil dispersants, in seawater. Based on the principle that oil dispersants decrease surface tension, a linear correlation was established between the dispersant concentration and surface tension. Thus, the dispersant concentration can be determined by measuring surface tension. The method can accurately analyze Corexit EC9500A in the concentration range of 0.5–23.5mg/L. Minor changes in solution salinity (<0.3%), pH (7.9–9.0), and dissolved organic matter (<2.0mg/L as TOC) had negligible effects on the measurements. Moreover, effects of extracts from marine sediments were negligible, and thus, the method may be directly applied to seawater–sediment systems. The method accuracy was confirmed by comparing with direct TOC analysis. This simple, fast, economical method offers a convenient analytical tool for quantifying complex oil dispersants in water/seawater, which has been desired by the oil spill research community and industries.
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